The present invention relates generally to fuel cut-off control systems for vehicles, and more particularly to a fuel cut-off control system that utilizes a series of crash sensors for detecting a fuel cut-off event, providing notice of the fuel cut-off event, and requiring manual reset of the system.
Fuel cut-off control devices and systems for internal combustion engines of vehicles are well known. These devices and systems typically are utilized for stopping the delivery of fuel to the engine in the event of a crash or various other fuel cut-off events.
Certain vehicles include a fuel pump with an inertia-actuated switch for cutting off power to the fuel pump when the switch is subjected to a substantial lateral pulse, e.g. a vehicle impact. This inertia-actuated switch can require that the driver manually operate the switch to reactivate the pump and allow the pump to continue delivering fuel to the engine. A drawback of these fuel pumps is that the inertia-actuated switch may not detect a vehicle impact event as efficiently as a series of electronic crash sensors. As a result, the fuel cut-off control system may fail to shut down the fuel pump under emergency conditions that require such action.
Other more recently developed fuel cut-off control systems do not include these inertia-actuated switch devices, but instead have a switch device, which is triggered by a series of more sensitive electronic crash sensors. These electronic crash sensors are beneficial because they can precisely detect the magnitude of a pulse from a substantial number of directions. Typically, these fuel cut-off control systems also include additional electronic circuitry for automatically resetting the fuel cut-off control systems. In this way, these systems do not require that the driver operate a switch conspicuously dedicated to returning the fuel supply system to an operational condition. For this reason, the delivery of fuel to the engine typically is continued without alerting the driver that the fuel supply has been cut off. By way of example, the fuel cut-off control system can include electronic circuitry for automatically resetting the system by merely requiring that the driver turn the ignition off and then on again.
A drawback of these automatically resetting systems is that they do not alert the driver of the potential damages resulting from the fuel cut-off event. In particular, as mentioned above, these automatically resetting systems typically do not notify the driver that the fuel supply has been cut off. In this regard, a typical driver could mistakenly believe that the vehicle is in a safe operating condition for the mere reason that he can restart the engine after the crash. However, the crash may have damaged the vehicle to the point that the vehicle requires repairs before it can be driven safely. For this reason, existing systems can provide the driver with a false sense of security and increase the risk of injury. For example, the crash can substantially damage a fuel line and allow fuel to leak from the vehicle. Such a result clearly presents a substantial fire hazard and a serious risk of injury.
Therefore, a need exists for a fuel cut-off control system that efficiently detects a fuel cut-off event, stops delivery of fuel to the engine, provides notice that the delivery of fuel has been cut-off, and requires manual reset.